R help - Oct 2012 - Chopping a two column data frame by rows into a three dimensional array.

If I have a two column data frame like:
> dat <- cbind("x"=c(1:100),"y"=c(100:1))
How can I create an array that splits every ten rows of that data frame
into a third dimension of an array so that:
> newarray[,,1]
,,1

x   y
1   100
2   99
3   98
...   ...
10  91


,,2

x    y
11  90
12  89
...   ...


...

Thanks.

	[[alternative HTML version deleted]]

HI,
May be this:
dat <- cbind(x=c(1:100),y=c(100:1)) 

newarray<-array(do.call(cbind,lapply(split(dat,rep(1:10,each=10)),function(x)
cbind(x=x[1:10],y=x[11:20]))),dim=c(10,2,10))
colnames(newarray)<-c("x","y")


?newarray[,,1]
? # ??? x?? y
?#[1,]? 1 100
?#[2,]? 2? 99
?#[3,]? 3? 98
?#[4,]? 4? 97
?#[5,]? 5? 96
?#[6,]? 6? 95
?#[7,]? 7? 94
?#[8,]? 8? 93
?#[9,]? 9? 92
#[10,] 10? 91
A.K.



----- Original Message -----
From: Hans Thompson <hans.thompson1 at gmail.com>
To: r-help at r-project.org
Cc: 
Sent: Monday, October 15, 2012 7:58 PM
Subject: [R] Chopping a two column data frame by rows into a three dimensional
array.

If I have a two column data frame like:
> dat <- cbind("x"=c(1:100),"y"=c(100:1))
How can I create an array that splits every ten rows of that data frame
into a third dimension of an array so that:
> newarray[,,1]
,,1

x?  y
1?  100
2?  99
3?  98
...?  ...
10? 91


,,2

x? ? y
11? 90
12? 89
...?  ...


...

Thanks.

??? [[alternative HTML version deleted]]

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aperm(array(dat,c(10,10,2)),c(1,3,2))
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Hans Thompson <hans.thompson1 at gmail.com> wrote:
>If I have a two column data frame like:
>
>> dat <- cbind("x"=c(1:100),"y"=c(100:1))
>
>How can I create an array that splits every ten rows of that data frame
>into a third dimension of an array so that:
>
>> newarray[,,1]
>
>,,1
>
>x   y
>1   100
>2   99
>3   98
>...   ...
>10  91
>
>
>,,2
>
>x    y
>11  90
>12  89
>...   ...
>
>
>...
>
>Thanks.
>
>	[[alternative HTML version deleted]]
>
>______________________________________________
>R-help at r-project.org mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.